Dictionary iteration in Python - Mini Project: Build & Apply

Dictionary iteration

📖 Scenario: You work in a small bookstore. You have a list of books with their prices stored in a dictionary. You want to check each book and its price to prepare a price list for customers.

🎯 Goal: Learn how to go through each item in a dictionary using a for loop and display the book names with their prices.

📋 What You'll Learn

Create a dictionary with book names as keys and prices as values

Create a variable to count how many books cost more than a certain price

Use a for loop with variables book and price to iterate over the dictionary items

Print the book names and prices in a readable format

Print the count of books that cost more than the given price

💡 Why This Matters

🌍 Real World

Bookstores and shops often keep product prices in dictionaries or similar data structures. Iterating over these helps prepare price lists or reports.

💼 Career

Knowing how to iterate over dictionaries is essential for data processing, reporting, and many programming tasks in software development and data analysis.

1

Create the books dictionary

Create a dictionary called books with these exact entries: 'Python Basics': 29.99, 'Data Science 101': 39.95, 'Machine Learning': 49.50, 'Deep Learning': 59.99, 'AI for Everyone': 24.99

Python

# Create the books dictionary with the given entries
# Your code here

Need a hint?

Use curly braces {} to create a dictionary. Put book names as keys and prices as values separated by colons.

2

Set the price threshold

Create a variable called price_threshold and set it to 40. This will help us count books costing more than this price.

Python

books = {
    'Python Basics': 29.99,
    'Data Science 101': 39.95,
    'Machine Learning': 49.50,
    'Deep Learning': 59.99,
    'AI for Everyone': 24.99
}
# Create price_threshold variable and set it to 40
# Your code here

Need a hint?

Just write price_threshold = 40 on a new line.

3

Count expensive books using a for loop

Create a variable called count_expensive and set it to 0. Then use a for loop with variables book and price to iterate over books.items(). Inside the loop, increase count_expensive by 1 if price is greater than price_threshold.

Python

books = {
    'Python Basics': 29.99,
    'Data Science 101': 39.95,
    'Machine Learning': 49.50,
    'Deep Learning': 59.99,
    'AI for Everyone': 24.99
}
price_threshold = 40
# Create count_expensive variable and set it to 0
# Use a for loop with book and price to iterate over books.items()
# Increase count_expensive by 1 if price > price_threshold
# Your code here

Need a hint?

Start with count_expensive = 0. Then write for book, price in books.items():. Inside the loop, use an if to check price and add 1 to count_expensive.

4

Print the books and count

Use a for loop with variables book and price to iterate over books.items(). Inside the loop, print the book and price in this format: Book: {book}, Price: ${price} using an f-string. After the loop, print Number of books costing more than $40: {count_expensive}.

Python

books = {
    'Python Basics': 29.99,
    'Data Science 101': 39.95,
    'Machine Learning': 49.50,
    'Deep Learning': 59.99,
    'AI for Everyone': 24.99
}
price_threshold = 40
count_expensive = 0
for book, price in books.items():
    if price > price_threshold:
        count_expensive += 1
# Use a for loop to print each book and price in the format 'Book: {book}, Price: ${price}'
# Then print the count of expensive books
# Your code here

Need a hint?

Use a for loop to print each book and price with print(f"Book: {book}, Price: ${price}"). Then print the count with print(f"Number of books costing more than $40: {count_expensive}").